tremolo as post event

[Mike Solomon]

Hey all,

Is there any way to create a tremolo as a post event?
I’m doing an arrangement for string quartet of a vocal piece and, at certain 
moments, I’d like to use tremolos.  So, for example,

{
c2
}

would become

{
  c2:32
}

Rather than doing:

{
  \tag #’vocal { c2 } \tag #’strings { c2:32 }
}

I’d like to do:

{
  c2\trem #32
}

and then define the function \trem differently in different files so that it 
appears in one and not the other.

As a stop gap solution I’m overriding the tremolo stencil to be ##f, but 
something about that seems unsatisfactory…

Cheers,
MS